The Palomar RX-100 R-X Noise Bridge tells you if you antenna is resonant or not, and if not, indicates whether it is too long or too short. It works with dipoles, inverted Vees, quads, Yagi beams, multiband trap dipoles and verticals. It works better than a dip oscillator because the frequency of measurement is set your receiver which is calibrated more accurately than a dip oscillator and is more stable. It is easy to use. Just connect the RX-100 to the antenna feed points (at the center of your dipole or base of your vertical). Then connect the RX-100 to your receiver with a coax line. Tune the receiver to the frequency at which you want to measure the antenna and turn on the noise bridge. You will hear a loud noise in the receiver. Now adjust the two knobs on the noise bridge for a null (noise minimum). Now read the knobs. The "R" knob reads the antenna feedpoint resistance directly in ohms. The "X" knob reads reactance. This device can be used to set your antenna tuner, test a balun, check tuned circuits and more!

Heavy cast aluminum case. Operates from 9 volt battery (not supplied). Early production is orange and later production is black.

Reminder: Do not accidently transmit into this device.
Do not turn on transmitter or let VOX turn it on when R-X Noise Bridge is connected to antenna.